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  2. Combined Air Emissions Reporting

Combined Air Emissions Reporting System (CAERS)

Introduction

CAERS is an application that allows industry from subscribed State, Local, or Tribal authorities (SLTs) to report their air emissions so you can:

  • Meet SLT-specific air emissions reporting requirements
  • Report air emissions annually and/or triennially per the Air Emissions Reporting Rule (AERR, 40 CFR 51) via your SLT.
  • Optionally, get a head start on reporting to the Toxics Release Inventory (TRI, 40 CFR 372), to be finished in TRI-MEweb when reporting shared toxic air emissions in the relevant form. 
Data Collection Authority
OMB Control No Title
2060-0580 Air Emissions Reporting Requirements (AERR) (Renewal)
2070-0212 Toxic Chemical Release Reporting (Renewal)
2060-0003 Prevention of Significant Deterioration and Non-Attainment New Source Review (Renewal)

This page contains resources for CAERS users (preparers, certifiers).  Please reach out to your SLT staff for guidance on specific State, Local, Tribal air emissions reporting requirements.

CAERS V6 User Guide

  • CAERS V6 User Guide (pdf) (7.9 MB, 01/03/2025)
  • CAERS Glossary of Terms (pdf) (648.84 KB, 3182022)
  • Default Heat Content Ratios for CAERS (pdf) (197.1 KB)
  • NEI-TRI pollutant crosswalk: Visit the Product Design Team page and find it under "State/Local/Tribal (SLT), National Emission Inventory (NEI), Toxic Release Inventory (TRI) Mapping"
  • Greenhouse Gas Reporting Program Emission Factors (xlsx) (131.23 KB, 02/05/2024)

CAERS V6 Trainings

Introduction to CAERS 

  • Welcome to CAERS for New Preparers and Certifiers (pptx) (8.2 MB, 12/16/2025)

  • Welcome to CAERS for New Preparers and Certifiers Video

User Interface

  • CAERS V6 User Interface Training Video

Bulk Upload

  • CAERS V6 Bulk Upload Training Video
  • CAERS V6 Bulk Upload Template Sample Demo1 (xlsx) (4.46 MB, 01/29/2025)
  • CAERS V6 Bulk Upload Sample Template Original Saved (xlsx) (4.46 MB, 01/29/2025)

Reporting Control Devices

  • CAERS V6 Control Devices Training (pptx) (6.48 MB, 02/13/2025)

CAERS V5 Trainings

Introduction to CAERS 

  • Mississippi

    • Welcome to CAERS for Mississippi
    • Welcome to CAERS for Mississippi (pptx) (9.88 MB, 12/14/2023)

User Interface

  • All Reporters
    • User Interface Training
  • District of Columbia: 
    • Monthly Reporting Part 1: Intro and Unit Process Setup
    • Monthly Reporting Part 2: Process & Calculation Method
    • Monthly Reporting Part 3: Non-Emission Factor Calculation Method
    • Monthly Reporting Part 4: CEMS, Certification & Submission

Bulk Upload

  • Bulk Upload Training
  • Sample Bulk Upload Template (xlsx) (4.47 MB, 1/31/2024)

Please note that excel downloads and uploads can take time if you have a large amount of data.  You may be able to upload and download faster if you convert your excel file to/from JSON format.  You may use an excel-JSON converter for this process.  If you would like to work in JSON directly, see instructions below.

Report via JSON Upload

  • CAERS JSON Reference Data (xlsx) (3.34 MB, 09/06/2023)
  • Open API Spec and Data Exchange Template (DET), scroll down to Resources in the Exchange Network site

CAERS Additional Resources

  • NAICS 2022:  This file contains a comparison of 2017 to 2022 NAICS:  NAICS 2017 to 2022 Comparison (xlsx) (214.12 KB, 02/23/2022) .   If NAICS for your facility have been discontinued, please contact your SLT to determine the most appropriate updated NAICS to use. 
  • Source Classification Codes Search and Download
  • WebFIRE Emission Factor Search and Download
  • Greenhouse Gas Reporting Program Emissions Factor Search and Download
  • Other Emission Factor Search (e.g. Landfill Emissions Emission Factors Estimation Tool LandGEM).
  • EPA National Emissions Inventory Reporting Codes 

CAERS V4 Trainings

These trainings are still valid but users should note that older screens appear in the trainings that may be different for the updated screens used in the current version of CAERS.

User Interface 

  • Georgia:  Opt In-Opt Out Process for Georgia DNR Facilities Video
  • Idaho:
    • Welcome to CAERS for Idaho (pdf) (3.55 MB, 12/08/2022)
    • Welcome to CAERS for Idaho Video
  • Maine:
    • Welcome to CAERS for Maine (pdf) (3.65 MB)
    • Welcome to CAERS for Maine Video
  • Rhode Island: 
    • Welcome to CAERS V4 for Rhode Island (pdf) (3.59 MB, 3/21/2023)
    • RI CAERS V4 Training 1 Video
    • Why Report HAPS video: RI CAERS V4 Training 2 Video 
    • Process Throughput in Hours video: RI CAERS V4 Training 3 Video
  • All Reporters:
    • Operating versus Shut Down Components Video
    • When and Why Must I Shut Down a Component? Video
    • Process, Fuel, Calculation Method, Alternative Throughput Video
    • Process Throughput in Hours Video
    • Temporarily Shutdown to Operating Process Video

Combined Air Emissions Reporting

  • Combined Air Emissions Reporting (CAER) Home
  • CAERS
  • SLT Resources
  • CAER Project
    • CAER Short Term Wins
    • Outreach from Previous Years
  • PDT Projects
Contact Us About Combined Air Emissions Reporting
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on April 8, 2025
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